The W3EDP Antenna

I have never operated 80m from my home. I have never had the space for a full half-wave dipole, and haven’t really had the motivation to put up anything else. Well, I’ve stumbled across something that may work—the W3EDP antenna.

The W3EDP is an 85-ft. end-fed wire with a 17-ft. counterpoise. Of course, you need an antenna tuner to make this work, but I already have a tuner or two here. And, if you’re going to operate QRP, a small tuner is even pretty easy to build.

Here are some links:

While Googling for information on the W3EDP, I also found a great article on building a current-type 4:1 balun on the N0SS website. The article was written by W1CG.

UPDATE 11/19/06: This afternoon, I strung an 85-ft. wire up into the trees, connected it to the T-1 longwire antenna tuner, and then put the antenna tuner on it. Several messages in the links above didn’t seem to think that the counterpoise was necessary for 80m, so I left it off.

The first readings were a bit perplexing. The SWR was jumping all over the place, and no matter what position I set the controls, I couldn’t get the SWR much below 3:1. Thinking that the 17-ft. counterpoise might be needed after all, I connected and fiddled with the tuner controls once again. This time, I was able to achieve an almost 1:1 SWR.

At this point, I decided to pack it all up and head back inside. It was gray and cold, had started to snow, I didn’t have an enclosure in which to stick the tuner, and the piece of coax that I had connected to the tuner wouldn’t reach to the shack anyway.

Overall, though, I was quite pleased with this experiment, and I think that it won’t be long before I’m on 80m.

Comments

  1. Where you able to get a W3EDP up and running?

    If so, how did it play?

    Thanks & 73 de Donald

  2. Funny you should comment on this item just now. Sunday night, I started thinking about this again. It was too late to get outside and hang wire, but I did measure and cut an the 85-ft. and 17-ft. sections.

    I also dug out of the junk box a random wire antenna tuner I bought many moons ago. It’s the SST Electronics T-1. I never got it to work back when I bought it, but now that I know a little bit more about how antennas work, and now that I have an antenna analyzer, I think I can get this all to play together.

    I’m unclear as to what to do about the counterpoise. Some articles say that it’s useless except on the 20m band. So, I might try it with the counterpoise, without the counterpoise, and with the coax shield connected to a eight-ft. ground rod I recently sunk just outside the shack.

    An amusing aside: I did a Google search for “SST Electronics,” and it appears that it morphed into a record company. Apparently, the founder of the company, Greg Ginn, started the company when he was a teenager and made ham radio gear. Later, he got interested in music, and turned SST Electronics into SST Records. See http://en.wikipedia.org/wiki/SST_Records for more details.

  3. UPDATE 11/19/06: This afternoon, I strung an 85-ft. wire up into the trees, connected it to the T-1 longwire antenna tuner, and then put the antenna tuner on it. Several messages in the links above didn’t seem to think that the counterpoise was necessary for 80m, so I left it off.

    The first readings were a bit perplexing. The SWR was jumping all over the place, and no matter what position I set the controls, I couldn’t get the SWR much below 3:1. Thinking that the 17-ft. counterpoise might be needed after all, I connected and fiddled with the tuner controls once again. This time, I was able to achieve an almost 1:1 SWR.

    At this point, I decided to pack it all up and head back inside. It was gray and cold, had started to snow, I didn’t have an enclosure in which to stick the tuner, and the piece of coax that I had connected to the tuner wouldn’t reach to the shack anyway.

    Overall, though, I was quite pleased with this experiment, and I think that it won’t be long before I’m on 80m.

  4. Hey Dan,

    How do you have the 17′ counterpoise connected to the wire? How is the counterpoise deployed?

    I’d like to put up a wire such as you have.

    Thanks!

    73 W1YB

  5. The counterpoise is attached to the ground terminal of the antenna tuner. I was also going to experiment with connecting this terminal directly to a ground rod, instead of using the counterpoise, and/or in addition to using the counterpoise, but just haven’t gotten around to it.

    73, Dan KB6NU

  6. Hi Dan — Enjoyed reading this. I just found the SST T-1 random wire tuner I bought in 1980 to tune the wires I used with the shortwave listening setup I had then. It worked well for me for several years, noticeably improving received signals. Thought I had lost the tuner long ago but it just turned up in a box of junk deep in my closet, so I looked it up online and found on Wikipedia the story of how SST, originally a manufacturer of ham gear, morphed into a record company. Fascinating. Now that I’m licensed, maybe I’ll even use the T-1 for its intended purpose for the first time. It’s got a little light or LED on the front. Can’t remember for sure, since I’ve never connected the thing to a transmitter, but the light glows on transmit either when you achieve a decent SWR match or when you haven’t. Guess I’ll get out my antenna analyzer and find out which. I remember from the long-lost instructions that this tuner is rated for up to 100 or maybe 125 watts.

    73/aloha.
    Ernie NH7L

  7. Dan KB6NU says:

    Ernie–

    The light bulb on the unit (it’s a neon bulb, I believe) is a (very) rough indicator of the output power You’re supposed to adjust the tuner for maximum brightness.

    Sunday night, I actually applied some power to the wire, and actually made a contact. I had some funny results, though. First of all, I set up the tuner on a window sill, and brought the random wire in directly to the tuner. I then connected the 17-ft. counterpoise to the tuner’s ground terminal and laid it out on the ground. I then connected my antenna analyzer and adjusted the tuner for minimum SWR at 3530 kHz. I was able to get it down to about 1.20:1.

    Next, I connected the coax to the IC-746PRO and cracked the power down to about 20W. WHOA!! The rig said the SWR was more than 3:1! I switched in the rig’s tuner, which brought the SWR down to 1.1:1, but I didn’t think that I’d have to use the 746′s internal tuner.

    I wasn’t sure that I should try to operate with this configuration, but I figured I’d give it a go. I tuned around and heard K2PMC calling CQ. He was 599, so I called him back. He copied me, and said I was S5-6. We had a nice QSO, but I cut it short, as I was still not very comfortable operating this way.

    The source of my unease is that never before has the SWR measured with the antenna analyzer disagreed so wildly with what the SWR measured by the radio. I’m not really sure what to make of it. One thing I’m going to try is to use a 66-ft. counterpoise, and if I get similar results, then connect the counterpoise to the 8-ft. ground rod I have just outside the shack window. As always, I’ll report on it here.

  8. UPDATE: 1/31/07
    Monday night, while gabbing with the guys on our club’s 2m net, I measured out 66 feet of wire and crimped a spade lug on it. Tonight, I ran outside, laid it out on the ground, and poked the lug through the hole in the window where I have my antenna tuner.

    What a difference this new counterpoise makes! The settings for lowest SWR are quite different than when I had the 17-ft. counterpoise connected, but this time, the SWR that I measure with the antenna analyzer agrees with the SWR measurement that the rig is making. At 3530 kHz, I was able to tune the wire so that the SWR was 1.1:1 and below 1.5:1 from 3500 to 3560 kHz.

    I made two contacts tonights. Both responded to my call of CQ. The first was with K1ARO in CT, running less than 20W. He was 599, and he gave me a 589 report.

    The second was with N8DJ in Edgarton, WV. He was 459, and he gave me a 559 report. Both QSOs were around 3530 kHz, and during both contacts the SWR measured by the rig was solidly 1.1:1 with the IC-746PRO’s internal tuner off.

    I don’t think this antenna is the world’s best performer—it’s kind of noisy, for one thing—but it’s very cool that I can get on the air again. It’s also very cool that I was able to use this antenna tuner that I’ve had kicking around my junk boxes for decades.

  9. Hello Dan,
    I was piqued to read of the SST T-1 longwire tuner. I met Greg Ginn in a smoky club as a mop topped 20-something punk rocker! He was playing first with Black Flag, then with Gone. Anyway, It’s very funny that he was a ham–a fact that I’ve always relished. Anyway, could you possibly take a photo (or several) of that longwire tuner? There is very little information available about Ginn’s activities as a ham, and this would really be an interesting little side-note in my hamming hobby.
    Pretty please with sugar on top?
    Thanks and VY 73,
    Jonathan KC7FYS/7J1AWL

  10. Dan & others,
    I too am using a random wire & it really works!. It’s 65 feet of #22 gauge black insulted wire attached to the ant tuner and another 65 ft length attacthed to the ant tuner ground terminal. Both wires are up about 20 ft. Used this first with an Icom 751A and now with a new icom 746Pro. I also use the Pro’s internal auto tuner so now I do not have to be so exact about the ant tuner setting. All SWRs are 1:1. No RF in the shack or in the house.

    All this wire and all this performance for just $12 at Radio Shack!
    73,
    Joel, N3GSE

  11. Chris K6DBG says:

    Dan,

    I’m very interested in your attempts here. I have a W3EDP strung up at my vacation QTH, and in good weather it is very pleasant to use connected directly to my KX1. But I would like to use it inside during bad weather, and have been trying to figure out how to achieve this.

    The W3EDP requires a tuner. It also seems to require a counterpoise – mine is happier with an array of tuned counterpoises, cut for each band (20/30/40). When I’m connected directly, the KX1 does a nice job of tuning it up.

    It doesn’t really like to be fed with a long length of coax, though – at least, the tuner doesn’t deal with it well. I’m thinking about putting a small remote tuner at the feedpoint, like what you’ve done. It won’t be very remote – within arm’s reach! W3EDP’s original tuner was *very* simple, but I’m lazy – I’d like it to be “automatic”. The Elecraft T1 might be the answer, but it’s pricey for a single application.

    Did you get your SST T-1 happy?

    Any other suggestions?

    73 de chris K6DBG

  12. Chris,

    If you read through some of the other replies, you’ll have noted that I did indeed get the antenna and tuner to work on 80m. I did this by connecting a 66-ft. counterpoise. So, this agrees with what you’ve done on the other bands, i.e. using 1/4-wave counterpoises.

    I’d say that a remote tuner at the feedpoint is the way to go. In effect, that’s what I have now, except that the tuner is not all that remote. It’s only about three feet away from the radio on the window sill.

    Some guys are using the SGC SG-239 in this type of application with decent results. I tried one here, but apparently, this particular tuner likes the counterpoise to be longer than the driven element. Since my wire is 85 feet long, and the counterpoise only 66 feet long, the SG-239 never found a good match. I still haven’t tried lengthening the counterpoise, and in fact, I think the counterpoise is actually shorter than 66 feet now, as my wife ran over it with the lawn mower sometime this summer.

    73, Dan KB6NU

  13. Hi Guys. I have been using the W3EDP antenna for about 4 summers now. The setup is from my trailer caravan. The rig is either the QRP+ or my FT817 both running into a home brew “T” tuner. The antenna and ground wires are connected directly to the tuner.
    The site I use mostly is a camping field about 150 ft AMSL on a chalk down so the topsoil is about 9 inches deep and drains quite quickly after rain. I have tried using just the 85 ft wire against a ground spike, not very sucessfully, but it certainly works best with the 17 ft counterpoise. Mostly used on 40 or 80 metres, and gives me a 1:1 vswr on both bands. The antenna is strung into a tall oak tree about 50 ft away.
    To stop the wires from tangling I have made up two reels about 1 inch diameter (cotton reels) with 4 inch dia cheeks of thin plywood. The reel is glued to one cheek and has a small nail in it to hook the wire to. The other cheek is loose but the assembly is held together with a machine screw and a wing nut on the other end. All the bits of wood are varnished to make them waterproof.
    To deploy the antenna I use a hard dog ball spiked through and attached to a long length of braided kite line. The ball is swung into the top of the tree and is just heavy enough to drop down through the foliage to where I can grab it, secure the end of the antenna to the other end of the line then haul the antenna up and into the tree usually with a bit of the wire pointing down by about 6 ft. The nylon cord stretches a bit to compensate for tree sway and the surplus is wound around the ball and secured to the ground with a tent peg. I think the setup works just great for /P work certainly around the UK. As the QTH is close to the east coast and our nearest neighbour across the water is Germany, at night I get 5/9+ from Europe.
    At the end of the day I haul down the antenna, wind it on its reel. Same with the counterpoise and the line is wound onto the ball and secured with an elastic band.
    Try it Dan. :-))

  14. Ric Haworth K5RIX says:

    Hi Dan, et al -
    I used a W3EDP while living in Navy Housing (not only no antennas allowed, no station allowed!) in Rhode Island with reasonable success. The wire feed end came in through a window screen and connected to a small Ten-Tec T-type tuner on the sill. The antenna simply laid over the roof ridge (composition shingle/wood roof) at about 15′ and terminated atop a 16′ fiberglass pole in the back yard. I’d guess the end 45′ or so was actually “in the air”! I cheated and used a kit-built Ten-Tec tunable artificial ground with the 17′ wire dressed around the baseboards in the shack for the counterpoise. With careful tuning, RF on the rig was not an issue. My station was never discovered.

    80M QRP was very good out to around 250 miles most evenings, and the other bands performed similarly with greater distance as the frequency increased. I was located on an island about 60′ above sea level, and the W3EDP at 15′ actually did pretty well on 10.1 MHz and higher, with lots of European, Caribbean, and even a few African stations worked on 30, 20, and 17.

    I first learned of the W3EDP in a wire antenna book from RSGB (sorry, I can’t remember the author’s name). The article on this antenna specifies the 17′ counterpoise be used on 40, 20,and 15, and no counterpoise on 80 or 10; no mention is made of the WARC bands. I had zero success with the 17′ counterpoise by itself. W3EDP apparently devised this antenna sometime during the 1930′s, so it is likely the original configuration worked just fine with vacuum tube finals and link coupling.

    If one can come up with a satisfactory solution to RF grounding, I think this is a most useful antenna in difficult situations or for temporary/portable operation. I’m going to put one up here for /patio portable and work it against the large steel awning. Have fun!
    73
    Ric K5RIX (ex-WI6I)

  15. I have had luck here in Tampa merely throwing a wire up into, and around a tree at it’s widest points, making in effect a big vertical loop. Feed it with 450 ohm line, and enjoy! You can play with the feed point, I like to pull my feed as high up in the tree as I can before it snags.

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